1 files changed, 55 insertions, 0 deletions
diff --git a/src/structure.c b/src/structure.c
new file mode 100644
index 0000000..a3039e7
--- /dev/null
+++ b/src/structure.c
@@ -0,0 +1,55 @@
+#include "structure.h"
+
+void traverse_structure(int group, int index, BoardUnit* board) {
+  board[index].structure_group = group;
+  for (int i = 0; i < 4; i++) {
+    int new_unit = index + NEIGHBOR_INCREMENTS[i];
+    if (board[new_unit].feature == board[index].feature && board[new_unit].structure_group == 0) {
+      traverse_structure(group, new_unit, board);
+    } else if (board[new_unit].feature == ANY && board[new_unit].structure_group != board[index].structure_group) {
+      board[new_unit].feature = board[index].feature;
+      traverse_structure(group, new_unit, board);
+      board[new_unit].feature = ANY;
+    }
+  }
+}
+
+void refresh_structure_groups(BoardUnit* board) {
+  for (int i = 0; i < BOARD_UNITS; i++) board[i].structure_group = 0;
+
+  int structure_group = 1;
+  for (int i = 0; i < BOARD_UNITS; i++) {
+    if (
+      board[i].structure_group == 0
+      && board[i].feature != EMPTY
+      && board[i].feature != SEPARATOR
+      && board[i].feature != 'F'
+    ) {
+      traverse_structure(structure_group, i, board);
+      structure_group += 1;
+    }
+  }
+}
+
+int evaluate_structure(int index, BoardUnit* board) {
+  int value = 0;
+
+  char feature = board[index].feature;
+  int structure_group = board[index].structure_group;
+
+  for (int i = 0; i < BOARD_WIDTH; i++) {
+    for (int j = 0; j < BOARD_WIDTH; j++) {
+      int index = translate_coordinate(i * BOARD_WIDTH + j);
+      if (board[index].feature != EMPTY) { // Empty tiles doesn't count
+        for (int k = 0; k < 4; k++) {
+          if (board[index + NEIGHBOR_INCREMENTS[k]].structure_group == structure_group) {
+            value++;
+            break;
+          }
+        }
+      }
+    }
+  }
+
+  return value;
+}